Just look underneath to see if you have airbags.

I'm going to see my indy mechanic in a few to have him diagnose. From what I have read, I think my problem is probably my sway bar end links. I am guessing these parts are the same whether you have the sport suspension or not, since the part look ups don't ask. I used the BMW PNPC program and found the best price for OEM on these is the BMW Parts Store for $40.56 (other places were as high as $62). I also saw several aftermarket for much less. FCP Euro has one for $6.09. Since that part is so much cheaper, I'm reluctant to put that on my X (made by Karlyn in Taiwan).

Are there any aftermarket options anyone would recommend, or should I just go with OEM for this?

OK, turns out it appears to be the inner bushings on my lower control arms. My mechanic said you probably can't just get the bushings because you usually wouldn't be able to press them into the control arm. Sure enough, I looked at the diagrams and they don't even list the bushing, so apparently I need to buy two control arms. Once again, cheapest OEM was BMW Parts Store for $160 each, and there are aftermarket ones ranging all the way down to $37.

Again, are there any aftermarket control arm brands anyone would recommend, or should I just bite the bullet and order OEM? Bav Auto has Lemfoerder for $120 and Meyle for $110. I have seen those brands as recommended on other parts.

The bushings can be pressed out and replaced but since you are not DIY bushings and the labor cost to replace them may exceed labor and part cost of purchasing the entire arm. Usually Original equipment manufacturer (OEM) parts are fine. I am not sure who makes BMW control arms.

Tim - are you talking about the "wishbone" control arm? Not the thrust arm (it has a ball joint on one side) -

If so, the OE brand is Lemforder - I'd honestly just go with a pair of those - do it right or do it twice - and address any other wear items in the front end because you'll prob need an alignment after.

FCP Euro is a lifetime warranty on all parts sold, and much cheaper than Bav Auto - $166 shipped for both, if these are the ones:

https://www.fcpeuro.com/products/bmw...r-31126760275l

That one you linked is the upper control arm. I need the lower control arm (also called 'tension strut'), part # 31126769717 & 718. I've seen a lot of places, including FCP, that have the Lemfoerder for $115-120 each. Importec has it for $96, but I've never dealt with them and their site looks fishy. I've also found a FEBI-BILSTEIN one for $98 from RMEuropean and they have the Lemfoerder for $100.

This part connects to the lower ball joint. My mechanic said they are probably fine, but I'm wondering if I should replace those at the same time. He said my sway bar end links look fine, which is what I originally thought the problem was. He also said there's a good chance I won't need to get an alignment if we just replace the upper control arm and it is a good part (exact same dimensions).

This is the part I need:

http://www.rmeuropean.com/Images/Big...9F178792-2.jpg

OK so you need the thrust arm - you can buy bushings for it, the upgraded BMW bushings are about $115 a pair - They are called "protection package" bushings:
https://www.ecstuning.com/BMW-E53-X5...l_Arm/ES49337/
https://c1552172.ssl.cf0.rackcdn.com/414194_x800.jpg


YES replace the ball joints too, they are shot at this point -

Don't try to save the $15 for Febi, just get the Lemforder pair.

Get 2 of these: https://www.fcpeuro.com/products/bmw...r-31126756491l

You could also go with the Meyle HD - I went with them a few years back and they have worked well for me, about $80 apiece -

https://www.fcpeuro.com/products/bmw...-31121096169my

https://www.fcpeuro.com/products/bmw...-31121096170my

I'm getting ready to order both control arms and two ball joints from RMEuropean. They won on price - Lemförder control arms for $100 each and Lemförder ball joints for $25 each, free shipping.

I had seen the name, but I didn't realize Lemförder was a division of ZF and they make a variety of OEM parts for BMW.

Yep this is true ^^ - Lemforder is the OEM for BMW

A pair of polyurethane bushing is only $65.00. You can cut out the old bushing with a hole saw and a sawzall. Here a post of the new polyurethane bushings installed in the thrust arm.

http://i426.photobucket.com/albums/p...pssds5mmiv.jpg

Here a video of removing the thrust arm from the lower ball joint with a ball joint tool.

https://www.youtube.com/watch?v=7_ekrGlb6To